MEDLINE Marks Its 45th Year

We’ve gone from 22 users to 601 million and from thousands to billions of searches. Check out what else has changed over the last 45 years.

**Notable MEDLINE Events, 1971-2016**
1971	2006 (Fiscal Year 2005 Statistics)	2016 (Fiscal Year 2015 Statistics)
236 indexed journals 1,222 indexed journals by September 1972	4,928 indexed journals	5,618 indexed journals
147,000 total citations for MEDLARS since January 1, 1969 490,000 total citations by September 1972	606,000 citations indexed 13,476,222 total citations	806,326 citations indexed 20,651,383 total citations (not counting the 2 million OLDMEDLINE-derived citations that all now have MeSH)
22 users	77 million PubMed unique visits	601 million PubMed unique visitors
70,000 searches/year by June 1972	754 million PubMed searches	2.8 billion PubMed searches (Web and API)
Operated on an IBM 360/50 mainframe computer	Ran on 20 Dell PowerEdge 1850 servers, 2 CPU 8Gb RAM, with the Linux operating system in 64-bit mode	Runs on approximately 62 standard Linux servers, each with two quad core 2.6-3.6 GHz Intel Nehalem CPUs, 48-64 GB of memory, 1TB of local storage, and a Gigabit Ethernet connection
Available via dial-up telecommunications for a fee	Available via the Internet World Wide Web	Still available free on the Internet World Wide Web